Rituximab treatment for steroid dependent or steroid resistant nephrotic syndrome in adult patients

Background: Minimal change disease (MCD) and focal segmental glomerular sclerosis (FSGS) are major causes of nephrotic syndrome (NS). The patients of steroid-dependent (SD) or steroid-resistant (SR) NS are exposed to high doses of steroid, more adverse effects, and worse outcomes. This study applied B cell-oriented rituximab therapy in MCD or FSGS adult patients with SD or SR, to investigate its efficiency and safety. Methods: Eight patients with steroid-dependent and frequent-relapsing (SD/FR) NS and six patients with steroid-resistant (SR) NS were enrolled. B-cell-oriented (<5 cells/mm 3 ) rituximab administration was used with single dose of 375 mg/m 2 adjusted according to eGFR. Results: During the follow-up period of 15.0 (8.8-18.0) months, B-cell depletion was achieved and maintained in all the 14 patients. Four, two, seven, one patients received two, three, four, five infusions of rituximab respectively. No adverse event was observed. All the eight SD/FR patients maintained complete remission without relapse. Six of them stopped steroid in 10 (2.3-12.3) months and four of them further stopped immunosuppressants. All of them maintained stable kidney function (eGFR 107.4 ± 27.4 vs. 111.0 ± 31.5 mL/min/1.73m 2 , P=0.600). All the six SR patients showed no response and presented with severe nephrotic syndrome. Five of them presented with kidney function deterioration (eGFR 49.6 ± 35.7 vs. 15.9 ± 11.5 ml/min/1.73m 2 , P=0.047) and three of them went into ESRD. Conclusion: B cell depletion-oriented regimen of rituximab was effective and safe for MCD or FSGS adult patients with SD/FR nephrotic syndrome, which could reduce drug doses and adverse events. This regimen showed no therapeutic effect for SR patients.